If as expected, they consent, it means the UK will still be “in” on May 23, meaning, under EU law, Britain will have to take part in the upcoming European Parliament elections.

If that happens, some Tory Brexiteers are threatening to behave like a wrecking ball in the EP, which has the powers to decide the EU budget and elect the new president of the European Commission, the all-powerful EU executive.

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“This is the 21st century, and you cannot hold a nation captive against their will,” Conservative Brexiteer Mark Francois told the EU on Tuesday.

If the extension, and with it the EP elections, go ahead “you will be facing perfidious Albion on speed”, he said, with a term used in the past to describe the British Empire as treacherous or deceitful.

On Wednesday he invoked the Greek myth about the hollow wooden horse Odysseus used to sneak his men into Troy to capture it from within.

“We will become a Trojan Horse within the EU and utterly derail all their attempts to pursue a more federalist project,” he said.

Prime Minister Theresa May acknowledged that participation in the EU elections – at an estimated cost of £108 million (US$140 million) – was now on the cards when she formerly triggered the EP elections Monday, and put out a search for candidates.

Only last month she said it would be “unacceptable” to take part in the poll for the 73 UK seats for the 751-member body, almost three years after the vote to leave the EU.

May added the proviso the elections will be cancelled at short notice if she manages to obtain parliamentary approval for her withdrawal agreement with the EU.

“We remain completely committed to delivering on Brexit, with both sides working hard to agreeing a way forward, appreciating the urgency in order to avoid European elections,” she said.

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But the prime minister has already tried three times to pass her deal through parliament and failed miserably.

Talks with the opposition Labour Party who want a softer Brexit have been going on for a week with no sign of a breakthrough.

Brexiteers desperate to break free from the rule of “unelected Brussels bureaucrats” now face a distinct possibility that Brexit will be settled by a plebiscite for the European Parliament.

“The European elections are a de facto 2nd referendum. If Leave supporting parties win a majority of seats, Brexit will go ahead. If Remain supporting parties win a majority… … Brexit is dead,” tweeted Diarmuid Scully, a Doctor of Political Science at the University of Limerick.

“One thing is fairly predictable, both the two major parties, the Conservatives and Labour will get clobbered,” said Quentin Peel, an associate fellow with the Europe Programme at the think tank Chatham House.

“That’s why they really don’t like this idea because they know they won’t do well.”

Few in Britain cared about the European Parliament elections in the past.

But concerns above all over immigration, and the notion the elections were more of a platform for protest than for policy led to the rise of the United Kingdom Independence Party (UKIP) returning the most seats in the last EP elections in 2014.

It was their success that drove then-Prime Minister David Cameron to call the EU referendum.

If the EP elections go ahead in the UK, the Conservative Party, already at breaking point over Brexit, is likely to take the hardest beating.

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Around third of Conservative MPs now want a hard crash out with no withdrawal agreement with Brussels, despite warnings from the civil service, the International Monetary Fund and the Bank of England that it would lead to economic catastrophe.

Unlike the first past the post system for national elections, the European Parliament vote is carried out under proportional representation, giving more of a chance to smaller parties.

There are already two “Brexit” parties, UKIP founded by Nigel Farage, Brexit’s political shock jock, and currently also a member of the European Parliament he holds with such disdain.

But he has left the party after it embraced the anti-Islam far-right, and formed the Brexit Party. Farage told The Sunday Telegraph that he would be putting up a list of “household names” from all walks of life.

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His party did not answer questions from South China Morning Post, asking who they were.

As the face and voice most associated with Brexit, Farage could soak up vast swathes of disaffected Tory voters.

“If we have to fight those European election on May 23, we’ll fight them because it’s time we taught them a lesson,” Farage says in a video campaign message.

EP elections could also punish the Labour Party, led by Jeremy Corbyn who supports Brexit, albeit a “softer” version.

But the majority of Labour Party members and young supporters want to remain in the EU, even if that choice was not reflected at constituency level during the 2016 referendum.

Many have now joined the campaign for a second referendum.

The EP elections could help them in their quest, giving them a chance to show their disapproval of Corbyn’s EU stance by voting instead for one of the “Remain” parties, like the new party ChangeUK set up by pro-EU Labour and Conservative lawmakers, who left their respective parties last month in protest at their parties’ position over Brexit.

There is the pro-EU and pro-independence Scottish National Party, the Liberal Democrats and the Greens who tend to do better in European elections than in national polls.

Then add to the mix an estimated 2.5 million EU citizens living in the UK who weren’t allowed to vote in the referendum, but who can vote in the EP elections.

There’s also the 1.2 million British citizens who live in other parts of Europe who were also excluded from the June 2016 vote, even though their lives have been most affected by the result.

If the “Remain” parties are able in the short time available to put up joint “remain” lists, then the political picture in the UK after the EP elections could look very different indeed.

And Brexit may after all, end up being cancelled.

There is another possible scenario in the sliding doors of contemporary UK politics, and the one probably most feared by the EU: that Conservative Party Brexiteers manage over the next few days to oust May from the leadership spot – opening the door to the Brexiteer former foreign secretary Boris Johnson.

Johnson was Brussels correspondent for The Daily Telegraph in the early 1990s, a paper for which he still writes for a hefty sum.

He created a school of EU reporting that created the Europhobia that led to Brexit.

“We cannot risk giving the keys of the EU’s future to a Boris Johnson, or a Michael Gove (another Brexit-supporting Conservative), the architects of the Brexit disaster,” tweeted Guy Verhofstadt, Brexit Coordinator for the European Parliament last week.

“A long extension would do exactly that.”

Fellow journalists with Johnson in Brussels sometimes mooted that his determination to ridicule the EU may have been due to filial rivalry with his father Stanley Johnson, who had been a senior European Commission official and a Conservative Member of the European Parliament.

Johnson the elder, a Remainer, who is also a well known TV personality in the UK, was one of the first to respond to May’s request for candidates for the May 23 EP elections.

Maybe the European Parliament elections will be his chance to settle family scores.

Additional reporting by Agence France-Presse